//
// Main Cairo support header file for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2025 by Bill Spitzak and others.
//
// This library is free software. Distribution and use rights are outlined in
// the file "COPYING" which should have been included with this file.  If this
// file is missing or damaged, see the license at:
//
//     https://www.fltk.org/COPYING.php
//
// Please see the following page on how to report bugs and issues:
//
//     https://www.fltk.org/bugs.php
//

/** \file Fl_Cairo.H
  Cairo is currently supported for the following platforms:
    Windows, macOS, Unix/Linux (X11 + Wayland).

  \note In FLTK 1.3.x this header file (Fl_Cairo.H) included the platform
    specific Cairo headers. This is no longer true since 1.4.0.

  This header file is platform agnostic. If you need platform specific Cairo
  headers you need to \#include them in your source file.

  To use FLTK's builtin Cairo support you need to <tt>\#include \<FL/Fl.H></tt>
  \b before you include any other FLTK header which is officially required anyway.
  Since FLTK 1.4.0 the preprocessor constants \p FLTK_HAVE_CAIRO and/or
  \p FLTK_HAVE_CAIROEXT are defined in \<FL/Fl.H> by including \<FL/fl_config.h>.
*/

#ifndef FL_CAIRO_H
#define FL_CAIRO_H

#include <FL/Fl.H>

# ifdef FLTK_HAVE_CAIRO

# include <cairo.h>

/**
  \addtogroup group_cairo
  @{
*/

/**
  Contains all the necessary info on the current cairo context.
  A private internal & unique corresponding object is created to
  permit cairo context state handling while keeping it opaque.
  For internal use only.
  \note Only available if one or both of the CMake options
        FLTK_OPTION_CAIRO_WINDOW or FLTK_OPTION_CAIRO_EXT is set (ON).
*/
class FL_EXPORT Fl_Cairo_State {
public:
  Fl_Cairo_State()
    : cc_(0)
    , own_cc_(false)
    , autolink_(false)
    , window_(0)
    , gc_(0) {}

  // access attributes
  cairo_t *cc() const { return cc_; }         ///< Gets the current cairo context
  bool autolink() const { return autolink_; } ///< Gets the autolink option. See Fl::cairo_autolink_context(bool)
  /** Sets the current cairo context.

      \p own == \e true (the default) indicates that the cairo context \p c
      will be deleted by FLTK internally when another cc is set later.

      \p own == \e false indicates cc deletion is handled externally
      by the user program.
  */
  void cc(cairo_t *c, bool own = true) {
    if (cc_ && own_cc_)
      cairo_destroy(cc_);
    cc_ = c;
    if (!cc_)
      window_ = 0;
    own_cc_ = own;
  }
  void autolink(bool b);                   ///< Sets the autolink option, only available with --enable-cairoext
  void window(void *w) { window_ = w; }    ///< Sets the window \p w to keep track on
  void *window() const { return window_; } ///< Gets the last window attached to a cc
  void gc(void *c) { gc_ = c; }            ///< Sets the gc \p c to keep track on
  void *gc() const { return gc_; }         ///< Gets the last gc attached to a cc

private:
  cairo_t *cc_;        // contains the unique autoupdated cairo context
  bool own_cc_;        // indicates whether we must delete the cc, useful for internal cleanup
  bool autolink_;      // false by default, prevents the automatic cairo mapping on fltk windows
                       // for custom cairo implementations.
  void *window_, *gc_; // for keeping track internally of last win+gc treated
};

/** @} */

#endif // FLTK_HAVE_CAIRO
#endif // FL_CAIRO_H
